61845813 has 12 divisors (see below), whose sum is σ = 94587948. Its totient is φ = 38805120.

The previous prime is 61845809. The next prime is 61845841. The reversal of 61845813 is 31854816.

It can be written as a sum of positive squares in 2 ways, for example, as 47238129 + 14607684 = 6873^2 + 3822^2 .

It is not a de Polignac number, because 61845813 - 2² = 61845809 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61845803) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 201958 + ... + 202263.

It is an arithmetic number, because the mean of its divisors is an integer number (7882329).

Almost surely, 2^61845813 is an apocalyptic number.

It is an amenable number.

61845813 is a deficient number, since it is larger than the sum of its proper divisors (32742135).

61845813 is a wasteful number, since it uses less digits than its factorization.

61845813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 404244 (or 404241 counting only the distinct ones).

The product of its digits is 23040, while the sum is 36.

The square root of 61845813 is about 7864.2108949341. The cubic root of 61845813 is about 395.4607942947.

The spelling of 61845813 in words is "sixty-one million, eight hundred forty-five thousand, eight hundred thirteen".